Introduction: From Research to Reform
Knife crime continues to devastate lives across the UK, disproportionately affecting young people—both as victims and perpetrators. As a pracademic with 34 years of frontline policing and safeguarding experience—one of the authors of the Met’s Children & Young People Strategy (2021–2025)—and as a researcher at Cambridge, I’ve seen the harm caused by reactive systems and missed opportunities.
This article draws on my policing career, strategic policy work, and my Cambridge University research into London’s most prolific young robbery offenders. Many of those responsible for serious violence were themselves victims of trauma and neglect. Knife crime isn’t just a criminal justice issue—it’s a child protection issue.
Understanding the Roots of Violence
Youth violence often begins with lived trauma. Poverty, exclusion, domestic abuse, school exclusion, and familial incarceration are recurring backdrops in the lives of those who later carry and use knives. Unless we act upstream—early, holistically, and collaboratively—we are left managing symptoms, not causes.
Life Course Criminology and the 'Power Few'
The earlier a child is exposed to adversity, the more entrenched criminality can become. My Cambridge research focused on 81 young Londoners arrested four or more times for robbery in 2019. They made up just 6.5% of under‑26s arrested for robbery, yet accounted for 24% of all such arrests. A clear 'power few' pattern emerged: high-harm, high-frequency offenders with deeply traumatic backgrounds.
Victim–Offender: Findings from Cambridge Research
In this cohort of 81 prolific offenders:
• 80% had been victims of crime themselves
• 63% had gone missing—over 12x the London average
• 49% were excluded from school
• 91% were known to social services
• 35% had an incarcerated family member
• Over 50% were gang-affiliated; 27% were involved in County Lines
These were children shaped by persistent harm and unmet needs. For many, knife-enabled robbery was a symptom of trauma, not its cause.
Read the full thesis here: https://link.springer.com/article/10.1007/s41887-021-00070-7
Children’s Homes, Care and Missing Episodes
One of the most urgent insights from my research was the scale of missing episodes among young robbery offenders. Many had lived in children’s homes and were reported missing frequently—sometimes daily—often returning with cash, burner phones, or signs of exploitation.
To tackle this, I was appointed the Met’s Lead Responsible Officer for Missing People and Child Exploitation. Working with my Detective Inspector Jo Clark (Met’s Child Exploitation Training Team) and Florence Kroll CBE at the Royal Borough of Greenwich, we co-produced a national training video for care home staff, embedded through Thrive—a trauma-informed framework supported by the London Innovation and Improvement Alliance (LIIA).
Care staff are often under pressure. But when missing episodes are treated as routine or behavioural, we miss critical opportunities to intervene.
Knife Crime Is Networked Harm
Knife crime doesn’t sit in isolation. It’s connected to County Lines, drugs, sexual exploitation, and organised crime. Too often, agencies fail to join the dots. Who is being repeatedly arrested? Who is recruiting and exploiting these children? Who profits from their harm?
Until we prioritise disrupting adult networks, we will continue to criminalise the exploited.
The Role of Race and Disproportionality
65% of my research cohort were Black. While many factors contribute, structural racism is clearly present—in school exclusions, stop and search, care placements, and access to services. We must embed anti-racist, culturally competent safeguarding into every layer of knife crime prevention.
Stop and Search: Targeted, Not Abandoned
Stop and search is vital for removing weapons but must be used with care. Done wrongly, it undermines trust. Done correctly—intelligence-led, respectful, and community-reviewed—it saves lives.
Over half of the 81 offenders I studied were gang-affiliated. Many carried knives out of fear. Searches should be data-driven and supervised. Police must be well-trained. And communities must understand that lawful, protective action is different from harassment. Support and accountability must go hand in hand.
Education, Neurodiversity and Pupil Referral Units: The Fork in the Road
Step into a Young Offender Institution and you’ll meet bright children with undiagnosed dyslexia, ADHD or autism. By Year 9 they’re excluded—then recruited.
PRUs can be turning points or entry points to crime. Schools need trauma-informed staff, neurodiversity assessments, and access to vocational paths. In the 1950s, technical colleges offered trades. We need them back.
It Starts with Healing
Trauma doesn’t stop at the school gate. If a child grows up in violence, they bring that trauma with them. Disruption is often a cry for help. We need more spaces for healing—art, sport, mentoring, and safe relationships.
It Takes a Village
Over 75% of the cohort experienced parental neglect. These weren’t isolated events, but long-term harm. We need to treat these children as victims of system failure, not just offenders.
As the proverb goes, it takes a village. Today, too many villages are silent.
A Roadmap to Change
We know what works.
Let’s act:
1. Target exploiters. Use confiscated assets to fund youth services.
2. Embed trauma-informed training in all frontline services.
3. Screen for neurodiversity early.
4. Incentivise employers to offer apprenticeships.
5. Share harm data across agencies.
6. Co-chair youth scrutiny panels on stop and search.
7. Expand Thrive trauma-informed practice nationally.
Strategic Policy Alignment
The Met’s Children’s Strategy (2021–2025) reflects this evidence. It embeds trauma-informed policing, a gravity matrix, and earlier diversion. Click here to find it: https://www.met.police.uk/SysSiteAssets/media/downloads/force-content/met/about-us/children-strategy/the-children-strategy-a4-final.pdf
Conclusion: What Happens to Them Matters
Knife crime is not inevitable. But prevention is more than enforcement. My research, policy work, and policing experience all say the same thing: support the 'power few'—the high-harm young people who need justice, stability and healing.
Ask not just what they’ve done, but what’s happened to them. That’s how we save lives.
Further Reading and Contact
Cambridge Thesis: https://link.springer.com/article/10.1007/s41887-021-00070-7
LinkedIn: https://www.linkedin.com/in/lorraine-hilder-31436227
Lorraine Hilder, Former Detective Superintendent, Metropolitan Police Lead on Child Exploitation and Missing Persons
